202
FXUS65 KFGZ 042000
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
100 PM MST Thu Jul 4 2024

.SYNOPSIS...Hot and dry conditions will continue for most of
northern Arizona into early next week. The chance for showers and
storms will be limited to the White Mountains through Monday,
with a slow return of monsoon moisture possible later next week.

&&

.DISCUSSION...A strong ridge centered near the California coast
will nudge slowly eastward over the next several days, resulting
in a heat wave over the southwest US. An Excessive Heat Warning
starts today below 4000 feet from Yavapai County to the Grand
Canyon and Page/Lake Powell areas. With the persistence of this
pattern in the latest model data, we have extended this warning
all the way through Tuesday evening, and will need to monitor it
each day for the need to extend even further unfortunately. The
northerly flow around the ridge is a dry one for our area. Surface
dewpoints have fallen off into the 20s for the majority of the
area, except southern Yavapai where some 40s/50s linger and a few
showers have developed this afternoon. This air mass is forecast
to dry even further for Friday with dewpoints of 5-10F along/north
of the Mogollon Rim which is just about unheard of for this time
of year. This dry air will actually help things cool off
overnight, and we have undercut the NBM guidance significantly in
the high country - some upper 30s are likely at the usual cold
spots (Bellemont, Tusayan) the next few nights. Winds will be
breezy from the north and northeast at times later this evening
through Friday, with some gusts to 25 mph mainly along/south of
the Mogollon Rim. For Sunday and Sunday night, gradients tighten
as a trough passes northeast of the region. Another round of
breezy winds is forecast, from the W-NW at 10-15 mph and gusts to
around 25 mph.

By the middle and latter parts of next week, there is some
indication that the center of the high pressure system will move
north or even northeast of the state. This could allow for a
modest moisture increase from the east, but confidence is low. For
now, we have mainly used a blend of model data which brings a
20-40% chance of showers and thunderstorms to areas along and
south of the Mogollon Rim with lower chances to the north. If this
doesn`t happen, the heat wave will continue.

&&

.AVIATION...Thursday 04/18Z through Friday 05/18Z...VFR conditions
with N/NW winds around 10 kts, becoming mainly light and variable
after 03Z. KSEZ will have gusty northeast winds (to 25 kts) at
night.

OUTLOOK...Friday 05/18Z through Sunday 07/18Z...VFR conditions
continue. Daytime winds N around 10 kts, becoming light and
variable overnight.

&&

.FIRE WEATHER...This afternoon through Saturday...Hot conditions,
with highs 5-10 degrees above normal. Isolated showers and
thunderstorms over Yavapai County into this evening and then over
southern Apache County Friday and Saturday. Winds north/northwest 5-
10 mph, becoming north to northeast on Friday, and then back to
northwest on Saturday. Minimum afternoon RH 3-12%, recovering
overnight to 15-30%.

Sunday through Tuesday...Hot and dry conditions continue. Slight
chances for showers and thunderstorms gradually increasing each day,
mainly over the eastern Mogollon Rim and White Mountains. North to
northwest winds on Sunday with gusts 20-25 mph. Minimum afternoon RH
5-15%, recovering overnight to 15-45%.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning until 8 PM MST /9 PM MDT/ Tuesday for
AZZ005-006-037.

&&

$$

PUBLIC...JJ
AVIATION...MAS
FIRE WEATHER...MAS

For Northern Arizona weather information visit
weather.gov/flagstaff